I PURCHASED A SECOND AR7 PAIR SPEAKERS

[Giorgio AR]

I bought my second AR7 pair (in total, now I have 17 pairs of Acoustic Research speakers!).
The first 5 photos illustrate the first couple and the back of a woofer: n ° series 01622/01623, woofer dated 73/07 (see in the photos the non original labels - already purchased original pair - and the woofers with the surround glued underneath the paper cone - they are ready to receive new surrounds that will be correctly pasted over the cone).
The next three photos illustrate the new pair just purchased (it has yet to arrive at my house) with serial number 16638/16639.
Both pairs are veneered in wood, of different colors and have canvas frames: 1622/3 in wooden slats and 16638/9 in masonite.
I am very happy with this new purchase!

 

[Giorgio AR]

They came to my house!
The foam surrounds have to be redone, all the speakers are OK.
I removed a woofer from the new AR7 pair and this is dated 73/19 or maybe 18 (I will have certainty when I will also remove the 2nd woofer), with a progressive number of the label on the cabinet: 16639.
In the photos there is also the stamp stamped on the woofer magnet of my first AR7 73/05 pair, with progressive number 1023 cabinet.
It should also be noted that the first pair of AR7s No. 1022 and 1023 have the abbreviation EQ and are produced at Houghton Regis, England, the second pair No. 16638 and 16639 have the abbreviation HQ and are produced at Amersfoort, Holland.
Below the photos

In the middle the AR7 of the previous pair for comparison

 

the date on the magnet of 1023 AR7 woofer

 

 

the date on the magnet of 116639 AR7 woofer

 

 

the date of the revision and refoam previous 00/05

 

 

 

England label

 

 

Holland label

 

Edited September 24, 2019 by Giorgio AR
captions to explain photos

[ra.ra]

Hi Giorgio - - - Both pairs of your AR-7's look very nice, and I like the fact that you have one pair each from England and Holland. Like yourself, I have two pairs of AR--7's, and one pair has woofer date stamps only a few weeks earlier than yours from the last weeks of 1972. Pics attached show this pair during re-foam restoration.

With your speakers, I am curious about two things. I would like to know if they used the blue 6uF Sprague capacitor; and I'm also interested to see the type of stuffing used inside the cabinets. 

[Giorgio AR]

Hi Ra.Ra, I saw your AR7 pairs, splendid and very well restored in every detail, even aesthetic, you love these wonderful speakers! 

The inside of all four AR7s is yellow glass fiber, given my slowness both 4 speakers for now rest in a closet, I haven't looked inside yet and I can't say which capacitors they use (certainly the AR4xa I have of 36 74 use blue sprague and the values I measured were 10.9 mF, so they stayed in the cabinets and the speakers work perfectly).
I take advantage of a question: the last pair of foam purchased over a year ago (and not used) by Vintage AR, had the internal lip on the cone of about 134 mm. too small, compared to 140 mm. or 145 mm. which I measured respectively on the original sizes of 200001-1 woofers and 538 AR7 woofers (these have the cone slightly larger than other 8 "woofers !!), I don't like this foam (all the other sizes purchased by Larry: 10 "and 12" are fine, 10 "ones are also perfect for mounting under the cone like in my AR48s woofers).
From whom to buy in USA in you the most correct foam, keep in mind that I have to redo the foam of 8 speakers: 4 x AR7, 2 x AR6 and 4 x AR18, I found various sellers on ebay selling foam surround (Looneytunes however does not sell in Italy), someone with an inner diameter of 137 mm. and others of 140 mm. which I think would be good, if you have an opinion or advice, it would be welcome.
I am not in a hurry and saw the purchase of several pieces (I also have to buy two pairs of 12 "foam) I wouldn't want to go wrong and throw away money for nothing (see the purchase from Larry, maybe the foam is good anyway, but aesthetically I would make the cone smaller than the view!).

Giorgio

[ra.ra]

I'm not quite sure who may be the best source for new foams, but you might want to read this recent thread on this exact topic. I cannot recall where I purchased the foams you see on my AR-7's, but I had at least eight 8" woofers to re-foam and I think I bought a dozen at that time. The foams you see on my AR-7's above have an inside dimension of 5.5 inches which is the equivalent of 140mm. You might consider contacting some forum members for a source in Europe - - I know there are people in England and Denmark and France with extensive experience with AR's 8-inch speaker models. 

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10939-ar-surround-suppliers-who-to-use/

I would not be surprised if your AR-7's have the Sprague caps - - these seem to have found their way into many of the Euro production speakers from the Classic era, but I've never seen Spragues in AR-18's. Thanks for your feedback on the fiberglass, and we'll look forward to your progress as your projects move forward. With AR-6's, AR-7's and AR-18's, you've got a fabulous collection of small loudspeakers.

 

[Giorgio AR]

22 hours ago, ra.ra said:

I'm not quite sure who may be the best source for new foams, but you might want to read this recent thread on this exact topic. I cannot recall where I purchased the foams you see on my AR-7's, but I had at least eight 8" woofers to re-foam and I think I bought a dozen at that time. The foams you see on my AR-7's above have an inside dimension of 5.5 inches which is the equivalent of 140mm. You might consider contacting some forum members for a source in Europe - - I know there are people in England and Denmark and France with extensive experience with AR's 8-inch speaker models. 

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10939-ar-surround-suppliers-who-to-use/

I would not be surprised if your AR-7's have the Sprague caps - - these seem to have found their way into many of the Euro production speakers from the Classic era, but I've never seen Spragues in AR-18's. Thanks for your feedback on the fiberglass, and we'll look forward to your progress as your projects move forward. With AR-6's, AR-7's and AR-18's, you've got a fabulous collection of small loudspeakers.

 

Thanks Ra.Ra, read the topic and I opened a new discussion on the 8" woofer foam, as you will see there are several differences and the AR7 woofer is unique in its features, so I would really like to look for a foam that is closer to the big cone than this speaker, as you will see the diameter of the paper cone is larger than 5 mm compared to the 200001-1 woofer (155 mm vs 150 mm).

This week I can't work on the AR7s, I sold my AR3a improved pair and I have to pack two very protective packages to ensure the safety of the speakers that are like new (with my pace and commitment I think I will work a week!) , after shipment of the AR3a imp. I will remove the AR7 fiberglass and I will check the capacitors by type and values. I am attaching the photo of the AR3a imp. removed with great difficulty from the "totem" where they were stacked and ready to be packed!

[Giorgio AR]

On 9/24/2019 at 10:51 PM, ra.ra said:

I'm not quite sure who may be the best source for new foams, but you might want to read this recent thread on this exact topic. I cannot recall where I purchased the foams you see on my AR-7's, but I had at least eight 8" woofers to re-foam and I think I bought a dozen at that time. The foams you see on my AR-7's above have an inside dimension of 5.5 inches which is the equivalent of 140mm. You might consider contacting some forum members for a source in Europe - - I know there are people in England and Denmark and France with extensive experience with AR's 8-inch speaker models. 

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10939-ar-surround-suppliers-who-to-use/

I would not be surprised if your AR-7's have the Sprague caps - - these seem to have found their way into many of the Euro production speakers from the Classic era, but I've never seen Spragues in AR-18's. Thanks for your feedback on the fiberglass, and we'll look forward to your progress as your projects move forward. With AR-6's, AR-7's and AR-18's, you've got a fabulous collection of small loudspeakers.

 

Hi ra.ra, I haven't been able to work on AR7s yet, but I found  photos of my  AR7 1622/1623 where you see the AR7 capacitor and it's a 6mF blue Sprague, I add two photos.
I'll update you when I start working on the speakers, I'm still looking for a foam that has a wider size on the cone contact!

[ra.ra]

On 10/13/2019 at 2:42 PM, Giorgio AR said:

....where you see the AR7 capacitor and it's a 6mF blue Sprague...

Thanks for the crossover pic confirming Sprague cap - - - I have not been inside many AR-7's, but this is the only configuration I've ever seen, and in both of my pairs, caps all measured good and I left it all original - - no cap replacement in either pair - - electrolytics still good after 45 years. 

[Giorgio AR]

On 10/14/2019 at 4:51 PM, ra.ra said:

Thanks for the crossover pic confirming Sprague cap - - - I have not been inside many AR-7's, but this is the only configuration I've ever seen, and in both of my pairs, caps all measured good and I left it all original - - no cap replacement in either pair - - electrolytics still good after 45 years. 

Ra.ra below you can find photos of the third pair of AR7, recently purchased, is the second assembled in Holland, completely original and untouched, unlike the two previous couples it is a late model with vinyl coating (the other 2 couples are covered in wood ), this one as well as the others has consecutive numbers on the labels.
The last photo shows the three AR7s together.

 

 

 

 

 

 

[Lucky Pierre]

Hi Giorgio,

Just popping to say I love my 7s mated with my KLH Twenty Seven receiver.  I listen to the combo daily in my kitchen.

Plus, I am cooped up and bored.

 

P

[ra.ra]

4 hours ago, Giorgio AR said:

....the third pair of AR7 ....... is a late model with vinyl coating ....... this one .....has consecutive numbers on the labels....

It is interesting to see the subtle changes throughout a product's years of production. Not only did the cabinet covering change from wood veneer to vinyl, but I notice a few other minor variations. Your third pair includes a rear-wired tweeter - - it is possible that the part number may have changed with this revision, but I believe it has the same diameter magnet structure as your front-wired versions, and neither tweeter utilized ferro-fluid. Also, I notice that your latest pair has that "Euro" speckled paint on the cabinet backside; and that the terminal panel with switch has been rotated 90°. In fact, I think your latest pair uses a different switch with plastic toggle. Consecutive serial numbers are mostly standard for AR-7's because they were shipped with two speakers in one box. You have a very fine collection.

4 hours ago, Lucky Pierre said:

I listen to the combo daily in my kitchen.

Perfect little kitchen speaker - - often small enough to place on top of upper cabinets.

[Giorgio AR]

8 hours ago, Lucky Pierre said:

I also love receivers, I have three from McIntosh and three from Sansui (I'm also a lover of radio and the receivers were born mainly for this)

4 hours ago, ra.ra said:

It is interesting to see the subtle changes throughout a product's years of production. Not only did the cabinet covering change from wood veneer to vinyl, but I notice a few other minor variations. Your third pair includes a rear-wired tweeter - - it is possible that the part number may have changed with this revision, but I believe it has the same diameter magnet structure as your front-wired versions, and neither tweeter utilized ferro-fluid. Also, I notice that your latest pair has that "Euro" speckled paint on the cabinet backside; and that the terminal panel with switch has been rotated 90°. In fact, I think your latest pair uses a different switch with plastic toggle. Consecutive serial numbers are mostly standard for AR-7's because they were shipped with two speakers in one box. You have a very fine collection.

Perfect little kitchen speaker - - often small enough to place on top of upper cabinets.

Ra.ra, I confirm the switch with a plastic lever and also the 90 ° rotation of the crossover panel.
The rear-wired tweeters have the same diameter magnet as the previous ones, subsequently they got the denomination 200005.
Between the three couples, there are differences in the grilles frames (in the older couple the frame is in wooden strips, the other two have a masonite frame with different cut) and in the linen texture.

 

 

[Giorgio AR]

On 9/24/2019 at 6:30 PM, ra.ra said:

Hi Giorgio - - - Both pairs of your AR-7's look very nice

Finally after almost three years I have finished the first pair of AR7, they are the same ones you see at the beginning of Topic !!
Yesterday the woofers received the new foam correctly glued to the outside of the cone (the previous owner had the foam glued under the cone) and returned to efficiency in their cabinets.
Here is the pair of AR7 above the older AR2.
My thoughts now go to Robert, ("ra.ra") to whom the photos of this beautiful couple are dedicated that he would have appreciated and certainly commented below ... as he loved to refine the 8" woofers, I left too the outer frame not painted in black.